1. The switch: BuM seems simple to install no ordinary switch that locks clean and also ensures reliable contact. I had on my old bike with BuM lighting already have the same problem, finally I've just left on the "Auto" position. At the wheel of my wife is a light of Basta: The switch does exactly what I expect from a switch. Should not be a work of art to build a switch so surely.
2. Day / Night Mode: Why ask the switchover is not in the same way as in the car? A digital switching from day to night mode I would find much more convenient than a pointless dimmed dipped in day mode. For this reason I would like to switch off the day often the light and then bothers me point 1 above.
3. The near-field illumination is likely to be slightly lighter, especially at low speeds.
Many Greetings